Vacuum bottle



April 15, 1941.

C. O. DUEVEL, JR

VACUUM BOTTLE Filed May 28, 1958 INVENTOR. (Ila/249$ Due e/fi: w I m ATTORNEY.

Patented Apr. 15, 1941 VACUUMI BOTTLE Charles 0. Duevel, Jr., Norwich, Conn, assignor to The American Thermos Bottle Company, Norwich, Conn, a corporation of Ohio Application May 28, 1938, Serial No. 210,562

4 Claims.

This invention relates primarily to the manufacture of vacuum bottles having a protected tip, and more particularly is directed to the construction of the outer blanks of such bottles in such manner as to enable the surplus silvering solution used to line the vacuum chamber as well as the vapors incident to the heating of the bottle after the vacuum chamber has been coated with the silvering solution to be more readily discharged therefrom, coupled With improved means for sealing the vacuum chamber after the silvering operation. In this construction, a metal seal or closure is provided to cover the opening in the outer blank, which seal may have a suitable aperture therein through which the vacuum chamber is adapted to be exhausted of air, and which seal is also adapted to have secured thereto the usual tubulation for connection with the exhausting apparatus; the invention is also directed to cutting off the exhaust tube after it has performed its function in such manner as to leave the tip in a protected position.

'With these general objects in mind, the principal objects of the invention are as follows, namely:

To provide a finished vacuum bottle in which the teat or tip remaining after the vacuum tube has been cut off, is not only surrounded by a protecting medium, but is practically non-breakable.

To enable the surplus silvering solution to be more readily discharged from the vacuum chamber after it has performed its function, than has heretofore been the case.

To provide means for readily discharging all of the vapors incident to heating the bottle to fix the silvering solution on the walls of the vacuum ill chamber and in this way insure a bottle free from condensed vapor which has failed to escape from the vacuum chamber.

To make bottles having an outside uniform length.

Other objects of my invention will be apparent from reading this specification in conjunction with the accompanying drawing.

Heretofore it has been the usual practice to draw off by suction the surplus silvering solution from the vacuum chamber after it has performed its function, through the same orifice as that provided for the vacuum tube. This practice has proven to be satisfactory in vacuum bottles having a uniformly round bottom and having the tip projecting therefrom without protecting means being provided therefor.

The idea of protecting means for tips of vacuum bottles is shown in Walker and Visscher Patcut #1,42l,325. In the Walker and Visscher bottle, the bottom of the central portionv of the outer Wall is depressed inwardly and has the tip centrally located in the depressed portion, which results not only in a protective medium for the tip, but also in an annular channel in the bottom of the vacuum bottle. This channel is an objectionable feature of this type of bottle because the presence of the annular channel makes it impossible in practice to draw all of the surplus silvering solution from the vacuum chamber, and some of it in consequence collects in this annular channel. Furthermore, the orifice through which the vapors from the silvering solution are intended to be discharged, when subjected to the heat treatment, did not efiiciently perform this function, because of its small size, as condensed vapor in the form of water collects in this channel. In vacuum bottles it is very desirable that there be no such result.

My improved bottle construction takes advantage of the good features of bottles of the type of Walker and Visscher and at the same time overcomes the objections which did much to militate against the success of this type of bottle.

The closure of my improved bottle construction may also be made without a tip protecting indentation.

In the accompanying drawing,

Figure 1 is a side view partly in cross section of a glass vacuum bottle having a metal closure covering the opening to the vacuum chamber, the bottle being in condition to be exhausted.

Figure 2 is a cross section of the lower end of the vacuum bottle before the closure has been applied thereto.

Figure 3 is a cross section of the lower end of the vacuum bottle with the closure applied thereto and the exhausting orifice sealed.

Figure 4 is a cross section of a vacuum bottle sealed by my improved means which is embodied in a metal container, and

Figure 5 is a perspective view of the closure together with the exhaust tubulation attached thereto.

Referring now in detail to the drawing in which similar characters refer to similar parts throughout, l0 represents the outer wall of a glass vacuum bottle and II the inner wall thereof. .Between these walls is the usual vacuum chamber l2. The outer wall ID of the bottle ends in a projection 13 providing a large opening 14 at the bottom of the bottle.

In order to close this opening I provide a metal closure which is generally indicated as I5. This closure is made up of a plate portion l6, and a tip enclosing dome portion l1. Extending through this dome is the aperture l8 adapted to be put into communication with exhaust means (not shown) through the tubulation l9.

The closure I5 is made of metal having a coefficient of expansion close to that of the glass of the bottle blank, and is adapted to cover the opening I4, and upon being heated to a proper temperature when in this position, will soften the glass cont-acting and in the vicinity thereof, thus effecting a tight weld of the closure to the glass.

Various compositions may be used for the body of the metal closure, and as suitable examples I may specify alloys of iron and nickel, iron and chromium, and iron, nickel, and cobalt. These metals are combined together in such proportions that the thermal expansion of the alloy has the correct value relative to the expansion coefficient of the glass blank. An example of expansion coefficients adaptable for use in practicing the invention is as follows: thermal expansions in cm./cm. length at 475 C'. produce an elongation in cm./cm. of 4800 l0 for the glass (lime glass being used), and 5100 10 for the closure. Itwill be understood that these figures are given merely as an example and not in a restrictive sense. It may also be mentioned that the closure l5 preferably shouldbe such that molten glass will easily wet the surface, so as to produce sealing contact of good adherence and be gas-free.

The tubulation 19 may be secured to the closure in communication with the orifice 18 before the closure is welded to the glass blank. The securing of the tubulation to the closure may be made by heating the glass and closure to a welding heat and pressing them together sufficiently to effect the weld without closing the orifice oi the closure or the glass tube. When the closure is secured in place on the bottle blank, and the glass tube is in position on the closure, the tubulation is communicated to the exhausting means and the vacuum chamber I2 is exhausted of air in any well known manner. While the bottle is in exhausted condition the tubulation is cut, as by a gas flame, leaving the tip 20 entirely within the dome ll which acts as a protecting medium for the tip.

I prefer to provide the bottle blank with a longer projection l3 than is absolutely required to practice my invention, in order that the length of the finished bottle may be controlled in its manufacture and thereby insure the production of a bottle of standard outer length without substantial variation. In order to attain this purpose, while the closure is heated and the glass is in welding condition, the closure is pressed inward to such extent as to effect a predetermined distance taken on a line at right angles to and between the horizontal parallel planes of the bottom of the closure and another portion of the bottle, as for instance its shoulder.

Before the closure is secured to the bottle, the vacuum chamber may be silvered in any well known manner which is usually done by the employment of a silvering solution brought into contact with the entire surface of the inner walls of the-vacuum chamber which solution is fixed, as byheating. 7

All of the surplus silvering solution is passed out of thebottle blank before the heat is applied to fixthe solution adhering to the walls of the vacuum chamber. Upon application of such heat bottle blank being so constructed as to be free from liquid holding pockets when the bottle blank is in upright position with the bottom of the bottle blank lowermost, the same may be readily, thoroughly and quickly drained of all surplus silvering solution.

In Figure 4, the bottle is fragmentarily shown in a metal casing in which 2| represents the casing and- 22 the annular shock absorber into which the projection l3 of the outer wall of the bottle rests, thus insuring the bottle against side shift.

in the metal casing.

I have shown and described what I believe to be the best embodiment of my invention. However, I do not wish to be limited in patent protection to the embodiment shown but what I desire to cover by Letters Patent is set forth in the appended claims.

I claim:

1. In a glass vacuum bottle, a vacuum bottle blank having an opening in its outer wall and a metal closure having a coefi'icient of expansion close to that of said wall, said metal closure having a central dome portion and an outer flange portion, said dome extending into the vacuum chamber of said bottle, said closure being secured to said wall over said opening, an orifice in said dome and means for closing said orifice.

2. In a glass vacuum bottle, a vacuum bottle blank having an opening in its outer wall and a metal closure having a coefficient of expansion close to that of said wall, said metal closure having a central dome portion and an outer flange portion, said dome extending into the vacuum chamber of said bottle, said closure being secured to said wall over said opening, an orifice in said dome and means for closing said orifice, said means being entirely within the inside area ofsaid dome.

3. In a glass vacuum bottle, a vacuum bottle blank having an opening in its outer wall, and a metal closure having a coeflicient of expansion close to that of said Wall, said metal closurehaving a central portion and an outer flange portion, said central portion extending into the vacuum chamber of the said bottle, said closure being secured to said wall over said opening, an orifice in said central portion and means for closing said orifice.

4. In a glass vacuum bottle, a vacuum bottle blank having an opening in its outer wall, and a metal closure having a coefficient of expansion close to that of said wall, said metal closure having a cental portion and an outer flange portion, said central portion extending into the vacuum chamber of the said bottle, said closure being secured to said wall over said opening, an orifice in said central portion and means for closing said orifice, said means being entirely within the inside area of said central portion.

CHARLES o. DUEVEL, JR. 

